Method of manufacturing artificial stone.



M. H. AVRAM.

' METHOD OF MANUFAGTURING ARTIFIGIAL STONE.

APILIOATION FILED APBJS, 1909. RENEWED D120. 6, m2.

1,102,851, I Patented July 7, 1914.

with the methods hitherto employed.

urrah sTArrns PATENT curios.

more x AVRAM, or unwromr, N. Y.,Ass1eNoa 'ro s'rannann srnrca Baron: MACHINERY comranr, or wrmmoron, nnnawans;

' METHQD OF mannsao'ronme ARTIFICIAL s ronni Application filed s in 5, 1909, Serial No. 457,920.

new and useful Improvements in Methods of Manufacturing Artificial Stone, of which the following is a specification. I

This invention relates to an improved method of manufacturing artificial stone or bricks from a mixture of sand, llme andfl cement to which a coloring agent added, if desired. y The invention comprises more part1cularly novelsteps in the manufacture of such I stones or bricks by means' of which a su-.:

perior intermixture of the several ingredi-Q ents is obtained at a smaller expenditure of I power so that stoneso-f higher quality arei produced at a lower cost than was the case? The main objectof my invention is to insure an easy and unobstructed conveyance of the mixed ingredients to the mold with- 1 out any liability of the mixture to adhere to 5 the feed channels, etc., or to harden before, reaching the mold. In order to obtain this desirable result, I separate from a previ-I ouslyprepa'red intimate mixture of the dry ingredients such a quantity as to be just: sufficient for the formation of one stone or brick. This separated quantity is carried to a small mixing apparatus in which the necessaryamount of moisture is added while thoroughly agitating the mass. The mois ture is introducedin theform of either steam or hot water so as to effect a proper heating of the mixture and to do away with all additional heating devices, while simul-- taneously' any adhering of the mixture to the feed channels, molds-and plungers iseflectively prevented. 1 have further'found that for producing adurable stone of great resistance to pressure and other influences, it is of considerable importance that sand be used which is composed of. grains of a; comparatively large size intermixed with particles of a smaller size. In this way, the

cavities formed intermediate the larger grains are filled out by the grains of smaller size, such relative arrangement of the particles taking place when pressure is-applied to" the mass. I may here add that the sand obtained from one stratum or locality is usually of uniform grain. If there is fcund Specification ofjLetters Patent.

may be, 1 to the relatively coarse sand a quantity of 'tion of one stone or brick.

Patented July 3?, dead,

Renewed December 6, 1912. serial No. #735,316.

a stratum of fine sand, such sand would be intermixed with coarse sand obtained from another stratum or locality. If, however, a stratum of coarse sand is found,'this coarse sand should be intermixed with fine's and. It istbis non-uniformity of the sand particles that I want to attain when speaking of producing a mixture of coarse and fine sand. If the usual sand of but'one grain is used, the'ainount of the binding agents eniployed is sufficient to completely fill the cavities between the." grains, but by adding fine sand or vice-versa, a homogeneous brick is "obtained which characterized by the entire absence of'inner cavities.

In carrying my improved method into practice, I proceed as follows :-l prepare a suitable quantity of perfectly dried sand preferably of different fineness, viz., a qiiantity of relatively coarse dried sand and a quantity of relatively fine sand, both kinds of such sand being stored individually. I further prepare the necessary quantities of hydrated line, cement and a coloring agent, taking particular care that these ingredients are finely pulverized and in perfectly dry state. From these conveniently and individually stored materials, there are {intermittently separated predetermined quantities which are thoroughly mixeduntil a uniform dry mass is obtained. From the lat ter, there is then separated precisely such a quantity as is just sufficient for the forma- To this comparatively small mass, 1 apply the necessary moisture at. high temperature by either add ing a predetermined quantity of .hot water or by. introducing steam into said mass while thoroughly agitating the same. The amount of moisture used shouldbe just sufficient to effect a perfect cohesion of the plastic material after compression takes place. After the moisture has been added and while the mass is still in its hot state, it is conveyed to the mold to be compressed without delay into the shape desired, whereupon the brick thus formed is carried to a steam chamber and subjected to the action of highv pressure I employ' the ingredients in thefol iowing proportions :10 to 20 parts-of coarse sand, 50 to 60 parts of fine sand,' v8 to 10 parts of of time before hydrated lime, 2 to 5 parts of cement, 2 to 5 parts of water, to which mixture the mess sury quantity of a coloring agent may be added according to the shade desired, though I do not want to limit myself to the above proportions. Also some of the ingredients me be omitted. or substituted by others wit out departing from the spirit of my invention.

In the accompanying drawing, I have diagrammatically illustrated an apparatus which may be used for carrying out my imroved method, although other e em loyed for the same purpose.

WI in suitable bins l0, ll, 12, 13 and 14:, there are contained fine sand, coarse sand, h ydrated lime, cement and a coloring agent respectively. All these ingredients are well dried, and the lime, cement and coloring agent should be finely pulverized. From the bins, the several materials descend into suitable measuring or weighin devices 15, 16, 17, 18 and 19, by means 0' which predetermined quantities are intermittently dumped into a dry mixer 20. The weighing devices may be of any convenient construction, for instance as shown in Patent No. 888,572 granted to me May 26th, 1908. The dry mixer may also have any suiteble construction, such a mixer being shown, for instance, in Patent No. 875,234 granted to me December 31st,-1907. After the above ingredients have been intimately mixed, the mixture thus obtained is by chutes 21 conveyed to weighing or measuring devices 22, each of which separates automatically at certain intervals such a quantity from. the mixture as is justsufiicient for-the formation of 21 single stone or brick. rated quantity is then dumped into a miniature mixer 23. In this relatively small mixer, hot wuter'or steam is. added to the mixture through pipes 24. From each miniature mixer, 23, the wet mass is fed into a mold 25 which, after having received its charge, is carried intermediate a pair of plungers 26, 27,whcre said charge is molded into the shape desired. The molded bricks are finally conveyed to a steam chamber (not shown), to become hardened or steam iii-- durated.

It will be seen that by my improved method, important advantages over the hitherto used are obtained. The ry ingredients may be kept for any length and after being intermixed, without the lime and cement losing their ce mcnting properties. As the'materials are in u perfectly dry state while being intermingled. in the large dry, mixer, and as but small amounts of the mi 'xtui'e thus formed are agitated in '4 wet condition, there occurs u considerable saving of motive power when compared with the metho s heretofore em ployed which depended upon mixing the methods devices may bulk of the mass in a wet state. It is also obvious that by introducing the moisture into a comperatively large mixture of dry ingredients, it will he quickly absorbed near its point of entrance into the mixture. As it is. however to the tendency of the powdery lime and cement to absorb and bind moisture, to subsequently withdraw said moisture from those parts of the been excessively applied, andto oonveyit to the unsuficiently wetted parts, the result of moistening the mass in bulk would be to obtain an utterly uneven mass. By applying the moisture to small segregated bodies of the dry mixture contained in miniature mixers, a uniformly moistened mass results. By introducing the moisture in a hot state, it more readily penetrates said bodies and thus through, while with cold moisture there always exists the tendency to form lumps.

hus a more uniform mass is obtained which in turn results in the formation of bricks of even structure and increased strength. It is further obvious that by adding the hot moisture to the smell amount of a se regated dry mixture, the moldable mass t us formed will more uniformly maintain its temperature until received by the mold, than if added to the dry mixture in bulk, which owing to its large surface will cool unevenly, so that the subsequently segregated small quantities will possess different temperatures which is obviously obhot moldable mass readily traverses the chutes between mixer and mold and does not adhere to the walls thereof. In this Way exactly like quantities of material are always delivered to the mold, so that the resulting bricks possess even density. I may further add that a uniform high temperature of the plastic mass has the additional advantage that the latter is compressible to a higher degree than attainable with a cold mass, and furthermore the chemical reaction isgreatest, at high temperature. Furthermore, as the majority of the various feed channels and practically impossible owing mixtureto which it has becomes evenly distributed therejectionsble. Further, I have found thzit the other devices are traversed by dry materials-whim the mass is I moistened in the miniature mixer near the end of the entire operation only, there will not be formed any deposits on the walls of said channels and other devices. Finally, as the small quantity separated from the dry mixture is moistened with steam or hot water immediately before being molded, the materials have no time to set previous to the molding operation. In this way, a perfect product is obtained, time and labor is saved,

and the power necessary for forming the stones is reduced to a minimum: I claim: l 1. Method of manufacturing sand lime bricks which consists in mixing dried bodies of sand, hydrated lime and cement in soilicient (manticies to form aplurality of bricks, the quantiig of cement being materially less than that oi the lime consecutively segregating from See dry mixture fixed. smaller bodies each suiiicient for making a single brick only, admitting to each segregated body a predetermined quantity of hot nioistux-e and simultaneously thoroughly agi .t-

said body, so as to form a plastic n'iass, noinpi'essing said mass into the shape desired whereby the cement efiecte a preliminary binding of the constituents of the con pressed mass, and steam-inclurating said compressed mass to efiect a thorough silica tion of the same. i

2 Method of manufacturing sand lune bnicks which consists in mixing driedbodies of sand and hydrated lime in sufiieient qnantities to form a plurality of loricks resame, so as to form plastic masses, coinpressing said masses into the shape desired,

and steam-in lurating said compressed.

masses:

M615 H, AVRAM.

Witnesses:

Ganmnn TIsoi-mn, ARTHUR E, ZILTMRE. 

